Thanks nahadef.
Can one just buy a house and rent out rooms (after obtaining the permit)? There is no zoning? I assume in most countries you can't do that very easily. If you buy a house you don't buy a hotel, in the same way as when you buy farmland you can't just build a house on it. If it's classified as farmland it's a big hassle to change the land use to residential industrial, etc.
Thanks ewww, but the websites you listed offer flats/rooms for rent. I found plenty of those. I want to buy a property.